The present invention relates to a video display having a display panel provided with anodes and cathodes arranged orthogonally to each other to form grids, and also to a manufacturing method for such a video display.
FIG. 5A is a plan view of a related art electroluminescent (EL) display panel in an active matrix drive type EL video display, and FIG. 5B is a cross section view taken along the line Bxe2x80x94B in FIG. 5A. As shown in FIGS. 5A and 5B, the EL display panel 11 includes a glass substrate 12, a plurality of anodes 13 formed on one surface of the glass substrate 12 opposite to the display surface of the EL display panel 11 so as to be arranged in rows, for example, a plurality of EL phosphor layers 14 formed in the form of matrix, an insulating layer (not shown) formed on the EL phosphor layers 14, and a plurality of cathodes 15 formed on the insulating layer so as to be arranged in columns, for example.
To drive the EL display panel 11, a drive circuit must be connected to the anodes 13 and the cathodes 15. To this end, the related art EL display panel 11 shown in FIGS. 5A and 5B is formed with an L-shaped region 16 along adjacent two sides of the EL display panel 11 as a dedicated region for electrical connection of the anodes 13 and the cathodes 15 to the drive circuit. Although not shown, electronic components constituting the drive circuit are mounted on a printed wiring board separate from the EL display panel 11, and wirings formed on the printed wiring board are connected at first ends to the electronic components and connected at second ends to the anodes 13 and the cathodes 15 in the L-shaped region 16.
However, in the related art EL display panel 11 having the L-shaped region 16 dedicated for electrical connection, no video image is displayed in this region 16. Further, if the area of the EL display panel 11 is large, the yield of such large EL display panels manufactured is reduced. In addition, the area of the EL display panel 11 that can be manufactured is limited.
Accordingly, it is desirable to planarly join a plurality of EL display panels 11 as shown in FIG. 6 to thereby display a single large-sized video image. However, since no video image is displayed in each region 16, the large-sized video image displayed on the plural EL display panels 11 planarly joined has discontinuities corresponding to the regions 16. That is, a large-sized video image with no discontinuities cannot be displayed by the configuration shown in FIG. 6.
Furthermore, since the electronic components constituting the drive circuit are mounted on the printed wiring board separate from the EL display panel 11, the total thickness of the EL display panel 11 and the printed wiring board is large, so that it is difficult to reduce the thickness of the entire EL video display using the related art EL display panel 11 mentioned above.
It is accordingly an object of the present invention to provide a video display which can display a large-sized video image with no discontinuities and can be reduced in thickness.
It is another object of the present invention to provide a manufacturing method for the video display mentioned above.
In accordance with an aspect of the present invention, there is provided a video display comprising a display panel having a plurality of anodes and cathodes arranged orthogonally to each other so as to form grids; a printed wiring board having a drive circuit with wirings for driving the display panel and a plurality of bumps for electrically connecting the wirings of the drive circuit to the anodes and the cathodes; and an adhesive layer for bonding the display panel and the printed wiring board to form a multilayer structure. That is, the anodes and the cathodes of the display panel are electrically connected through the bumps to the wirings of the printed wiring board, and the display panel and the printed wiring board are bonded together through the adhesive layer. With this structure, the display panel is not required to have any dedicated region for electrically connecting the anodes and the cathodes of the display panel to the drive circuit for driving the display panel. Further, the total thickness of the display panel and the printed wiring board is small.
Preferably, the drive circuit comprises a plurality of electronic components mounted on one surface of the printed wiring board for driving the display panel, and the bumps are formed on the other surface of the printed wiring board. That is, the electronic components for driving the display panel are mounted on one surface of the printed wiring board opposite to its bump forming surface. With this structure, the electronic components for driving the display panel are integrated with the display panel.
In accordance with another aspect of the present invention, there is provided a manufacturing method for a video display, comprising the steps of preparing a display panel having a plurality of anodes and cathodes arranged orthogonally to each other so as to form grids; preparing a printed wiring board having a drive circuit with wirings for driving the display panel and a plurality of bumps for electrically connecting the wirings of the drive circuit to the anodes and the cathodes; forming an adhesive layer on any one of one surface of the display panel on which the anodes and the cathodes are provided and one surface of the printed wiring board on which the bumps are provided; and electrically connecting the anodes and the cathodes through the bumps to the wirings and bonding the display panel through the adhesive layer to the printed wiring board. That is, the anodes and the cathodes of the display panel and the wirings of the printed wiring board are electrically connected together through the bumps, and the display panel and the printed wiring board are bonded together through the adhesive layer. Accordingly, it is possible to manufacture a video display in which the display panel is not required to have any dedicated region for electrically connecting the anodes and the cathodes of the display panel to the drive circuit for driving the display panel, and the total thickness of the display panel and the printed wiring board can be reduced.
Preferably, the manufacturing method further comprises the step of mounting a plurality of electronic components for driving the display panel on the other surface, opposing to the surface with bumps, of the printed wiring board. That is, the electronic components for driving the display panel are mounted on one surface of the printed wiring board opposite to its bump forming surface. Accordingly, it is possible to manufacture a video display in which the electronic components for driving the display panel are integrated with the display panel.
Other objects and features of the invention will be more fully understood from the following detailed description and appended claims when taken with the accompanying drawings.